1、Designation: B695 04 (Reapproved 2016)Standard Specification forCoatings of Zinc Mechanically Deposited on Iron and Steel1This standard is issued under the fixed designation B695; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the
2、 year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S. Department of Defense.1. Scope1.1 This specification cove
3、rs the requirements for a coatingof zinc mechanically deposited on iron and steel basis metals.The coating is provided in several thicknesses up to andincluding 107 m. The seven thickest classes are usuallyreferred to as “mechanically galvanized.”1.2 This standard does not purport to address all of
4、thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.NOTE 1The performance of this coating complies with the require-ment
5、s of Specification A153/A153M and MIL-C-81562.1.3 The values stated in SI units are to be regarded as thestandard. The inch-pound equivalents of SI units are given forinformational purposes.2. Referenced Documents2.1 ASTM Standards:2A153/A153M Specification for Zinc Coating (Hot-Dip) onIron and Stee
6、l HardwareA194/A194M Specification for Carbon Steel, Alloy Steel,and Stainless Steel Nuts for Bolts for High Pressure orHigh Temperature Service, or BothA325 Specification for Structural Bolts, Steel, Heat Treated,120/105 ksi Minimum Tensile Strength (Withdrawn2016)3A490 Specification for Structural
7、 Bolts, Alloy Steel, HeatTreated, 150 ksi Minimum Tensile Strength (Withdrawn2016)3A563 Specification for Carbon and Alloy Steel NutsB117 Practice for Operating Salt Spray (Fog) ApparatusB183 Practice for Preparation of Low-Carbon Steel forElectroplatingB242 Guide for Preparation of High-Carbon Stee
8、l for Elec-troplatingB322 Guide for Cleaning Metals Prior to ElectroplatingB487 Test Method for Measurement of Metal and OxideCoating Thickness by Microscopical Examination ofCross SectionB499 Test Method for Measurement of Coating Thicknessesby the Magnetic Method: Nonmagnetic Coatings onMagnetic B
9、asis MetalsB571 Practice for Qualitative Adhesion Testing of MetallicCoatingsB602 Test Method for Attribute Sampling of Metallic andInorganic CoatingsB697 Guide for Selection of Sampling Plans for Inspectionof Electrodeposited Metallic and Inorganic CoatingsB762 Test Method of Variables Sampling of
10、Metallic andInorganic CoatingsF1470 Practice for Fastener Sampling for Specified Me-chanical Properties and Performance Inspection2.2 Military Standard:MIL-C-81562 Coating, Cadmium, Tin Cadmium and Zinc(Mechanically Deposited)42.3 AISC Standard:Specifications for Structural Joints Using ASTM A325 or
11、A490 Bolts53. Classification3.1 ClassesZinc coatings are classified on the basis ofthickness, as follows:1This specification is under the jurisdiction of ASTM Committee B08 onMetallic and Inorganic Coatings and is the direct responsibility of SubcommitteeB08.06 on Soft Metals.Current edition approve
12、d Nov. 1, 2016. Published November 2016. Originallyapproved in 1982. Last previous edition approved in 2009 as B695 04(2009). DOI:10.1520/B0695-04R16.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStand
13、ards volume information, refer to the standards Document Summary page onthe ASTM website.3The last approved version of this historical standard is referenced onwww.astm.org.4Available from Standardization Documents Order Desk, DODSSP, Bldg. 4,Section D, 700 Robbins Ave., Philadelphia, PA 19111-50985
14、Available from American Institute of Steel Construction (AISC), One E.Wacker Dr., Suite 700, Chicago, IL 60601-2001, http:/www.aisc.org.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1Class Minimum Thickness, m110 10780 8170 6965 6655
15、 5350 5040 4025 2512 1288553.2 TypesZinc coatings are identified by types on the basisof supplementary treatment required, as follows:Type IAs coated, without supplementary treatment (Ap-pendix X2.1).Type IIWith colored chromate conversion treatment (Ap-pendix X2.2).4. Ordering Information4.1 Supply
16、ing the following information by the purchaser tothe seller in the purchase order or other governing documentwill make the application of this specification complete:4.1.1 Class, including a maximum thickness, if appropriate,type, and for Type II, color and need for supplemental lubricant(3.1, 3.2,
17、and 6.2.5),4.1.2 Nature of substrate (for example, high-strength steel),need for stress relief (6.2.1), and cleaning precautions to befollowed (6.2.2 and 6.2.3),4.1.3 Significant surfaces (6.3),4.1.4 Requirements for and methods of testing for one ormore of the following, if required: need for and t
18、ype of testspecimens (8.1), thickness (6.3 and 8.3), adhesion (6.4 and8.4), corrosion resistance (6.5 and 8.5), absence of hydrogenembrittlement, and the waiting period before testing and testingloads (6.6 and 8.6),4.1.5 Inspection responsibility (Section 11) and samplingplan for each inspection cri
19、terion (Section 7), and4.1.6 Requirements for certified report of test results (Sec-tion 10).5. Workmanship5.1 The coating shall be uniform in appearance and free ofblisters, pits, nodules, flaking, and other defects that arecapable of adversely affecting the function of the coating. Thecoating shal
20、l cover all surfaces as stated in 6.3 including rootsof threads, thread peaks, corners, recesses, and edges. Thecoating shall not be stained or discolored throughout to anextent capable of adversely affecting appearance as a func-tional requirement. However, superficial staining, that resultsfrom ri
21、nsing or drying, and variations in color or luster shallnot be cause for rejection.NOTE 2The nature of the mechanical plating process is such thatcoatings characteristically will not be as smooth or as bright as someelectroplated coatings.6. Requirements6.1 AppearanceThe coating as deposited shall h
22、ave auniform silvery appearance, and a matte to medium-brightluster.6.2 Process:6.2.1 Stress-Relief TreatmentAll steel parts that have anultimate tensile strength of 1000 MPa and above and thatcontain tensile stresses caused by machining, grinding,straightening, or cold-forming operation shall be gi
23、ven astress-relief heat treatment prior to cleaning and metal deposi-tion. The temperature and time at temperature shall be 190 615C for a minimum of3hsothat maximum stress relief isobtained without reducing the hardness below the specifiedminimum.6.2.2 High-strength steels (which become embrittled
24、whencharged with hydrogen) and that have heavy oxide or scaleshall be cleaned before application of the coating in accordancewith Practice B242. In general, nonelectrolytic alkaline,anodic-alkaline, and some inhibited acid cleaners are preferredto avoid the risk of producing hydrogen embrittlement f
25、rom thecleaning procedure.6.2.3 For low-carbon steels, see Practice B183. Usefulguidelines are also given in Guide B322.6.2.4 Mechanical deposition of zinc coatings shall consist,in general, of all of the steps listed below, and in the sequenceas shown:6.2.4.1 Preparation of the surface of the parts
26、 to be coated,by chemical (generally acidic) procedure to an extent thatpermits uniformly satisfactory results from subsequent steps.6.2.4.2 Deposition of a thin metal coating, generally ofcopper, by immersion in appropriate chemical solutions, with-out the use of electric current. There are no thic
27、kness require-ments for this coating.6.2.4.3 Tumbling of the parts that have been treated accord-ing to 6.2.4.1 and 6.2.4.2 in a container with the following:(1) The zinc metal to be deposited, in powder form;(2) Impact media, which includes glass, for example, orother substances that are essentiall
28、y inert to the chemicals ofthe deposition process. The function of this media is to aid inproviding mechanical forces to drive the metal powder onto thesubstrate parts;(3) A “promoter” or “accelerator” which aids in the uni-form deposition of the metal powder; and(4) A liquid medium, generally water
29、.6.2.4.4 Separation of the parts from the solid and liquidmedia.6.2.4.5 Rinsing.6.2.4.6 Drying.6.2.5 Supplementary Treatments:6.2.5.1 Colored Chromate Conversion Treatments (TypeII)Colored chromate conversion treatment for Type II shallbe done in a solution containing hexavalent chromium ions.This s
30、olution shall produce a bright or semi-bright continuous,smooth, protective film with a uniform color that is capable ofranging from yellow through bronze and olive-drab to brownand black and that are capable of being dyed to a desired color.Bright dips that do not contain salts that yield films con
31、taininghexavalent chromium ions are precluded as treatments forproducing Type II coatings.6.2.5.2 Waxes, lacquers, or other organic coatings are notprohibited from being used to improve lubricity, and the needfor them shall be supplied in the purchase order or othergoverning document (see 4.1.1). Su
32、pplemental lubricationB695 04 (2016)2treatments shall not be used to ensure conformance to the saltspray corrosion resistance requirements (see 8.5.4).6.2.5.3 Lubrication of grade DH nuts processed in accor-dance with this specification and used with Specification A325high-strength bolts is a requir
33、ement of paragraph 6.5 ofSpecification A325 and paragraph 4.8 of Specification A563.NOTE 3Although not included in Specification A194/A194M, thisprovision should apply to mechanically galvanized Specification A194/A194M 2H nuts when supplied for use with Specification A325 bolts.NOTE 4Specifications
34、 for structural joints using Specification A325 orA490 bolts references the use of lubricants on nuts to be used withSpecification A325 high-strength bolts and is found in the commentary onthis RCSC (Research Council on Structural Connections of the Engineer-ing Foundation) Specification, within the
35、 paragraphs entitled “Effect OfGalvanizing Upon Torque Involved In Tightening” and “Shipping Re-quirements For Galvanized Bolts and Nuts,” published November 1985,page 30.56.2.6 Surface DefectsDefects and variations in appear-ance in the coating that arise from surface conditions of thesubstrate (sc
36、ratches, pores, roll marks, inclusions, etc.) and thatpersist in the finish despite the observance of good metalfinishing practices shall not be cause for rejection.NOTE 5Applied finishes generally perform better in service when thesubstrate over which they are applied is smooth and free of torn met
37、al,inclusions, pores, and other defects. It is recommended that the specifi-cations covering the unfinished product provide limits for these defects.Ametal finisher can often remove defects through special treatments, suchas grinding, polishing, abrasive blasting, chemical treatments, and elec-tropo
38、lishing. However, these are not normal in the treatment stepspreceding the application of the finish. When desired they must bespecified on the purchase order (4.1.2).6.3 Thickness:6.3.1 The thickness of the coating everywhere on thesignificant surfaces shall be at least that of the specified classa
39、s defined in 3.1.6.3.2 Significant surfaces are defined as those normallyvisible (directly or by reflection) that are essential to theappearance or serviceability of the article when assembled innormal position; or that are capable of providing the source ofcorrosion products that deface visible sur
40、faces on the as-sembled article. When necessary, the significant surfaces shallbe indicated on the drawing for the article, or by the provisionof suitably marked samples.NOTE 6The thickness of mechanically-deposited coatings varies frompoint-to-point on the surface of a product, characteristically t
41、ending to bethicker on flat surfaces and thinner at exposed edges, sharp projections,shielded or recessed areas, interior corners and holes, with such thinnerareas often being exempted from thickness requirements.6.3.3 When significant surfaces are involved on which thespecified thickness of deposit
42、 cannot readily be controlled, it isincumbent upon the purchaser and manufacturer to recognizethe necessity for either thicker or thinner deposits. Forexample, to reduce buildup in thread roots, holes, deeprecesses, bases of angles, and similar areas, the depositthickness on the more accessible surf
43、aces will have to bereduced proportionately.NOTE 7The coating thickness requirement of this specification is aminimum requirement; that is, the coating thickness is required to equal orexceed the specified thickness everywhere on the significant surfaces.Variation in the coating thickness from point
44、 to point on a coated articleis an inherent characteristic of mechanical deposition processes.Therefore, the coating thickness will have to exceed the specified value atsome points on the significant surfaces to ensure that the thickness equalsor exceeds the specified value at all points. Hence, in
45、most cases, theaverage coating thickness on an article will be greater than the specifiedvalue; how much greater is largely determined by the shape of the articleand the characteristics of the deposition process.In addition, the average coating thickness on articles will vary fromarticle to article
46、within a production lot. Therefore, if all of the articles ina production lot are to meet the thickness requirement, the average coatingthickness for the production lot as a whole will be greater than the averagenecessary to ensure that a single article meets the requirement.6.4 AdhesionThe zinc coa
47、ting shall be sufficiently adher-ent to the basis metal to pass the tests specified in 8.4.6.5 Corrosion Resistance:6.5.1 The presence of corrosion products visible to theunaided eye at normal reading distance at the end of thespecified test periods stated in Table 1 shall constitute failure,except
48、that corrosion products at edges of specimens shall notconstitute failure. Slight “whisps” of white corrosion, asopposed to obvious accumulations, shall be acceptable.NOTE 8Mechanical deposition is exclusively a barrel-finishing pro-cess. It is recognized that mechanical deposition on parts may ther
49、eforeproduce surfaces that have a different characteristic from those on partsthat are finished exclusively by racking. Similarly, corrosion testing ofactual parts may produce different results from those on test panels. Saltspray requirements that are appropriate to indicate the technical qualitywith which a process is carried out may be impractical for acceptance ofactual parts. In such cases the purchaser shall indicate his requirements onthe purchase order (4.1.4).NOTE 9In many instances, there is no direct relation between theresults of an accelerated corro
